ASoC: tpa6130a2: Fix unbalanced regulator disables

This driver has unbalanced regulator_disable when doing module loading and
unloading. This is because tpa6130a2_probe followed by tpa6130a2_remove
calls twice tpa6130a2_power(0). Fix this by implementing a state checking
in tpa6130a2_power.
Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

sound/soc/codecs/tpa6130a2.c

@@ -125,7 +125,7 @@ static int tpa6130a2_power(int power)
 	data = i2c_get_clientdata(tpa6130a2_client);
 
 	mutex_lock(&data->mutex);
-	if (power) {
+	if (power && !data->power_state) {
 		/* Power on */
 		if (data->power_gpio >= 0)
 			gpio_set_value(data->power_gpio, 1);
@@ -153,7 +153,7 @@ static int tpa6130a2_power(int power)
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val &= ~TPA6130A2_SWS;
 		tpa6130a2_i2c_write(TPA6130A2_REG_CONTROL, val);
-	} else {
+	} else if (!power && data->power_state) {
 		/* set SWS */
 		val = tpa6130a2_read(TPA6130A2_REG_CONTROL);
 		val |= TPA6130A2_SWS;